Cardiac Pathology Flashcards
What is the most common type of heart disease and leading cause of death?
Coronary Artery Disease
Increasing age, Male gender, Hypertension, Hyperlipedemia, Cigarette Smoking & Diabetes are risk factors for what?
Coronary Artery Disease/Ischemic Heart Disease
List the most common sites of atherosclerotic disease in the heart in increasing order
LAD > RCA > LCX > LCA
Distinguish a R. vs. L. dominant heart
R. Dominant - Posterior descending artery is supplied by R. coronary A.
L. Dominant - Posterior descending artery is supplied by L. circumflex A
Substernal chest pain (crushing, stabbing, squeexing); pain that radiates to neck jaw or schoulder; Rapid, weak pulse; profuse sweating; nauseas & vomiting; dyspnea and discomfort are all classic clinical features of what?
Myocardial Infarction
Causes of Coronary Artery Disease
Atherosclerosis
Coronary artery emboli
Myocardial vessel inflammation (vasculitis)
Vessel spasm
What is the most sensitive and specific biomarkers of myocardial damage
Cardiac troponin T and I
They are proteins that regulate calcium mediated contraction of cardiac muscle
What proteins are used to determine myocardial damage but are not gold standard
Creatine kinase MB heterodimer - is sensitive but not specific for cardiac injury
Myoglobin - It is nonspecific for cardiac injury
elevation of cardiac enzymes in a typical assay is seen as early as _____, _____ returns to normal after 48 to 72 hours and troponin remains elevated for _____
3 hours
CK-MB
>5 days
Occlusion of the LAD causes infarction of what?
Apex, LV anterior wall & anterior 2/3 of septum
Occlusion of the circumflex A. causes infarction of what?
L. ventricular lateral wall
Occlusion of the RCA causes infarction of what?
RV, LV posterior wall, posterior 1/3 of septum
At what point are the following irreversible histologic changes seen in a MI seen:
- Slight waviness of fibers
- Very early coagulation necrosis and edema
- Coagulation necrosis increases with loss of nuclei, hypereosiniophilic
- Neutrophil infiltrate, yellow tan infarct
- Presence of Macrophages
- Scar tissue is being laid down
- Scarring complete and consists of a dense scar
- 30 mins - 4 hrs
- 4 hrs - 12 hrs
- 12 hrs - 24 hrs
- 1 - 3 days
- 3 days - 1 week
- 1-2 weeks
- 2 months
What is the time frame and characteristics of the early complications of an MI
First 24 hours
- Life threatening arrhythmias (V fib)
- Contractile/Cardiogenic Dysfunction (Shock)
What is the time frame and characteristics of the intermediate complications of an MI
2-4 days and up to 2 weeks
- Rupture: free wall, septum and papillary muscles
- Acute fibrinous pericarditis
What is the time frame and characteristics of the late complications of an MI
After 2 weeks
- Chronic pericarditis (Dressler Syndrome)
- Ventricular aneurysm
- Continued risk of heart failure and life threatening arrhythmia
What is the number one cause of death due to an MI & when does it typically occur
Arrhythmias, specifically ventricular fibrillation w/in 1 hour of onset
What is it called when there’s a rupture of the free wall, leading to blood accumulation in the pericardial space. This makes it hard for the heart to adequately fill during diastole because of the pressure of the blood in the pericardial sac and can ultimately lead to hemodynamic collapse
Acute pericardial tamponade
Increase age, first MI, absence of LV hypertrophy are all risk factors for what
Myocardial rupture - transmural infarct 2-4 post MI
What is Dressler Syndrome & it’s symptoms
Chronic fibrinous pericarditis due to immune reaction to myocardial proteins in blood.
Symptoms include fever, pleuritic pain, pericardial effusion
What is Chronic ischemic heart disease (IHD)
A state of heart dysfunction as a result of late complication of a MI which can lead to congestive heart failure and sudden cardiac death
Transient, often recurrent chest pain induced by myocardial ischemia but insufficient to induce myocardial infarction is known as what
Angina Pectoris
What are the three clinical variants of Angina
- Stable Angina
- Prinzmetal Variant Angina
- Unstable Angina
What causes the pain in Angina Pectoris
Lack of oxygen to tissues leads to the release of adenosine and bradykinin causing pain
Stable angina is characterized by: Stenotic occlusion of \_\_\_\_\_ arteries - Clinical manifestations include \_\_\_\_\_\_\_ - Relieved by \_\_\_\_\_\_\_ - Induced by \_\_\_\_\_\_\_
Coronary arteries
- Substernal pressure, squeezing, burning
- Relieved by rest or vasodilators
- Induced by physical activity
_______ variant angina is characterized by:
- Episodic _______
- Relieved by _______
- Unrelated to physical activity, HR or BP
Prinzmetal variant angina is characterized by:
- Episodic coronary artery spasm
- Relieved by vasodilators
- Unrelated to physical activity, HR or BP
Define unstable angina
Angina which is present at rest or angina that increases in frequency or duration (crescendo pattern)
STEMI corresponds pathologically to what
Transmural infarction (All layers of heart) & ST elevation in EKG
Since NSTEMI and unstable angina both cause partial occlusion of coronary vessels, how can they be distinguished?
Presence or absence of troponin. If present then it’s an NSTEMI
What is the second most common cause of death in car crashes
Aortic rupture - Typically at weaker points in aorta where the pulmonary artery is tethered by the ligamentum arteriosum
What is the most common cause of arrhytmias & what do the other factors have in common
Ischemic heart disease/CAD
Almost any structural alteration can result in a conduction abnormality
What is it called when the SA node is unable to generate a high enough heart rate commensurate with physiologic needs leading to symptomatic bradycardia
Sick sinus syndrome
What is the etiology of Atrial fibrillation & what are it’s risk
Independent and sporadic depolarization of myocytes with variable transmission to the AV node. This leads to a irregular contractile pattern.
The ineffective pumping of blood causes stasis which can lead to clotting and thrombus formation
What is the most common cause of sudden death after exertion
Long QT syndrome –> Torsades de pointes
What is the most common cause of sudden death due to ischemia induced arrhythmia & what are the risk factors in younger patients?
Coronary artery disease
- Drug abuse (cocaine, methamphetamine)
- Hereditary conduction abnormalities
- Hypertrophic or dilated cardiomyopathy
- Myocardial hypertrophy
- Myocarditis
- Mitral valve prolapse
Distinguish between systolic and diastolic dysfunction
systolic dysfunction - Increased oxygen demand
Diastolic dysfunction - Inability to relax heart muscles
Systolic dysfunction leading to heart failure has to do with what?
Lack of pumping ability leading to decreased ejection fraction
What are some causes of systolic heart failure
- Ischemic heart disease - Decreased cardiomyocytes causes the heart to not be able to pump as strongly
- Hypertension & Aortic stenosis - Ischemic changes can cause the pump to not be functionally as effective against increased pressure over the long term
- Dilated cardiomyopathy - Ventricles are too dilated to pump well
- Severe mitral regurgitation
Diastolic dysfunction leading to heart failure has to do with what?
Heart cannot adequately fill but ejection fraction can be normal - less filling means less blood being expelled
What are some causes of diastolic heart failure
- Hypertension & Aortic stenosis - Concentric L. ventricular hypertrophy decreasing ventricular space
- Hypertrophic cardiomyopathy - Decreases ventricular space
- Restrictive cardiomyopathy (fibrosis) - Decreases compliance of cardiac muscles
What are the clinical manifestations of Left heart failure
- Decreases tissue perfusion –> Decreased cerebral & renal perfusion
- Pulmonary congestion/edema - cough, crackles, wheezes, tachypnea
- Orthopnea
- Tachycardia
- Exertional dyspnea
- Cyanosis
- Paraoxysmal Nocturnal dyspnea
What is the classic chest x-ray image finding & histologic sign for L. CHF
Kerley B lines on X-ray
Hemosiderin-laden macrophages (due to extravasated RBCs)
What are the causes of R. heart failure
- Left heart failure
2. Cor pulmonale (lung disease/dysfunction) - any cause of pulmonary hypertension
What are the clinical manifestations of R. heart failure
- Liver & splenic congestion –> hepatosplenomegaly
- Distended juglar veins
- Effusions - peritonel, pleural & pericardial spaces
- Edema
- Extertional dyspnea
